Page Ruler

Draw a ruler to get pixel dimensions and positioning, and measure elements on any web page.

Page Ruler lets your draw out a ruler to any page and displays the width, height and position of it.
Features
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* Draw a ruler to any page and view the width, height and top, bottom, left and right position
* Drag the edges of the ruler to resize it
* Use the arrow keys to move and resize the ruler
* Show guides extending from the ruler edges
* Manually update the size and position of the ruler from the toolbar to make precision changes
* Enable "Element Mode" to outline elements on the page as you move your mouse over them
* Navigate through parents, children and sibling elements of any measured element
Important
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To use on local pages you will need to enable the "allow access to file URLs" option in your extensions tab
Support
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If you have any questions or wish to report a bug please use the 'Support' link in the Details tab above.